"Our investigators found end caps, which usually indicate a pipe-bomblike device," Beary said. "We believe this was not designed to cause significant property damage or injuries."

By that time, the FBI and the Bureau of Alcohol, Tobacco, Firearms and Explosives had decided that the Sheriff's Office was qualified to conduct the investigation on its own.

Pipe bombs can be as simple as gunpowder and a paper fuse, such as a large homemade firecracker, or as sophisticated as remotely detonated devices packed with commercial explosives. Mailboxes across Central Florida occasionally are destroyed by teenagers who build what amount to large firecrackers.

"This event is every bit as important as a neighborhood-mailbox bombing," said sheriff's spokesman Capt. Mark Strobridge in discounting any chance that the Disney explosion was a significant threat to public safety.

A recent case handled by the Sheriff's Office involved much more sophisticated pipe bombs found inside and outside a home on Wekiva Springs Road. A Volusia County man has been charged with making and planting those bombs.

What investigators found at Disney was a damaged garbage can. Descriptions varied throughout the day from "dumpster" to a large garbage can still small enough to be loaded by hand into a truck.

"The detonation did not damage anything beyond putting at least two holes in the trash container and damaging its hinged doors," Cpl. Susan Soto said in a written statement. "It resulted in no injuries. . . . Early evidence suggests that this was an isolated incident and that the device was not intended to hurt anyone."

The investigation is expected to last several weeks, according to the Sheriff's Office.

Downtown Disney is a popular shopping and entertainment complex that includes Downtown Disney Marketplace, Pleasure Island and Downtown Disney West Side. It drew attention recently when a crackdown on teenage loitering drew accusations of racial profiling from ejected teens' parents.

While Beary discounted any danger posed by Monday's explosion, he said security has been increased countywide because of the recent terrorist activity overseas.

"Once we saw things unfolding in the U.K. and Glasgow, and the fact that it's July Fourth, we increased security," Beary said. "This is not connected to any sophisticated [terrorist] plot, either domestically or internationally."